Chaser-holder for thread-cutting tools



June 7, 1938 A. F. B|'E|TF.x\1sTEn-ll l CHSER HOLDER4 FOR THREAD CUTTINGTOOLS 2 Sheets-Sheet l Filed June 7, 1937 June 7, 1938. l A. F.BRElTl-:NsTElN CHASER HOLDER FOR THREAD CUTTING TOOLSh Filed June 7,1937 2 Sheets-Sheet 2 Patented June 7, 1938 UNITE-D STATES PATENT OFFICEAlbert F. Breitenstein,

New Haven, Conn., as-

signor to The Geometric Tool Company, New Haven, Conn., a corporation ofConnecticut Application June 7, 1937, Serial No. 146,765

14 Claims.

This invention relates to improvement in Chaser-holders for mountingthread-cutting chasers in thread-cutting tools, such, for instance, asin self-opening die-heads.

One of the objects of the present invention is to provi-de a superiorChaser-holder by means of which the thread-cutting capacity of athreadcutting tool may be conveniently altered.

A further object is to provide chaser-holding means whereby aself-opening die-head or the like may be utilized for cutting a widerange of thread diameters without requiring the replacement of oneChaser-holder by another.

Another object is to provide a superior chaserholder of the characterreferred to whereby various thread diameters may be cut by employing ina given self-opening die-head or the like ychasers havingsubstantiallythe same length.

A still further object is to provide a superior chaser-holder by meansof which it will be neces'- sary to stock only chaser-blanks ofsubstantially the same dimensions in order to cut a range of threaddiameters with a given thread-cutting tool.

Still another object of the present invention is to provide superiorChaser-holding means Whereby, in Order to effect a change-over fromcutting right-hand threads to cutting left-hand threads, or vice versa,it will not be necessary to replace an entire Chaser-holder. f

With the above and other objects in view, as Will appear to thoseskilled in the art from the present disclosure, this invention includesall features in the said disclosure which are novel over the prior art.

In the accompanying drawings, in which certain modes of carrying out thepresent invention are shown for illustrative purposes:

Fig. 1 is a view mainly in side elevation and 4o partly in section of aself-opening die-head equipped With Chaser-holders embodying the presentinvention; Y

Fig. 2 is a view thereof in front elevation Fig. 3 is a fragmentarysectional View taken on the line 3-3 of Fig. 2;

Fig. 4 is a similar view taken on the line 4 4 of Fig. 2;

Fig. 5 is a sectional view taken on the line 5 5 of Fig. 3;

Fig. 6 is a front-face View of one of Vthe-chaserholders, detached, andshowing a chaser mounted therein; Y

Fig. 7 is a perspective View of the base-member of the Chaser-holder,looking mainly toward `the 55 forward 4face thereof;

drawings a self-opening die-head having the forward face of its bodyprovided With four (more or less) T-shaped guide-grooves 2|, each ofwhich is adapted to receive and guide for reciprocation the T-shapedguide-tang 22 of a reciprocating base-member, generally designated bythe numeral 23, and including, in addition to the l tang 22, justreferred to, a forward sector-shaped plate-portion 24.

Inasmuch as each of the four body-members 23 corresponds to each other,a description of one thereof, together with its associated parts, willserve for all.

The outer end of each of the body-members 23 is formed with an inclinedcam-surface 25 which is adap-ted .to be engaged by a similarly-inclinedinternal cam-surface 26 formed within the forward end of a ring-likeoperating-sleeve 2l. The said operating-sleeve encircles the body 23 ofthe die-head and is adapted to slide axially upon the same to controlthe radial movement of the Chaser-holder. moved forwardly it acts toforce the various body-members 23 bodily inwardly and to maintain thesame in such position. When the said Chaser-operating sleeve 2l' ismoved rearwardly, each of the body-members 23 of the chaserholder andthe parts carried thereby will be permitted to move radially outwardinto a retired position in a manner hereinafter described.

Each body-member 23 is urged outwardly by a pair of cup-shaped plungers28-28 (Figs. 1, 3 and 4), each of which is adapted to reciprocate in asuitable substantially-radial bore 29 formed in the body 2D of thedie-head structure directly back of the guide-groove 2l in .the latter.Each plunger 28 is urged outwardly by a helical spring 30 and engageswith a thrust-pin 3|, two of which latter project rearwardly from eachof the body-members 23.

When .the operating-sleeve 21 is zov The detailed character of thevarious die-heads l slight advancement or retirement of the basemembers23 and the parts carried thereby, byV

means of an adjusting-nut 32 mounted upon the threaded portion 33 of theshank 34 of the diehead structure. Y

On each of the respective opposite sides of the tang 22the rear face 35ofthe plate-portion 24 of the base-member 23 is adapted to ride upon thefront face of the body 28 of the die-head structure as is particularlywell shown in Figs.

1 and 4, Each base-member 23 is formed onA itsV forward face witha'substantiallywadial guidegroove 36 which is adapted to receive asubstan- V tially-radial guide-rib 31 projecting from the rear Vzo Vguide-rib 31V just above referred to is formed with a plurality oftransverse locating-teeth 39 which are adapted to selectively intertwith similar butforwardly-extending locating-teeth 48 formed upontheforward face of the headportionv 4I; of a locating-stud. 42. TheYlocating-stud 42 just referred to is firmly seated in aforwardly-opening counter-board recess 43 formed in the base-member23centrally of the groove 3B therein as particularly well shown in Figs.4 and '7. The said locating-,stud is retained in place by an anchor-Aing-pin 44 extending therethrough and through the adjacent portion ofthe tang 22 of the basemember 23. Y'

The base-member 23 on each of the respective oppositeY sides of theradial groove 35VV therein is formed with a threaded bore 45/receivingthe threaded shank of a clamping-screw generally designated by thereference'character 43 and having its outer end located in acounter-bored slot 41 in the chaser-mounting member 38 so as'thusarranged serve to rmlyrattach the chaser'.-

. Vmounting member 38 to the base-member 23 so that the guide-rib 31 ismaintained in the guidet groove y38 tor'thus restrainthe member 38 fromtwisting` with Yrespect-to the member 23 in a Y plane parallel withthercoacting faces of the two Y spect to thebase-'member 23.

FormedV YinrthefirnnerY contracted edge' of the i chaser-mounting member38 is a chaser-receiving notch 48 which .extends fromV front to ,rear

through the said member and'isrbounded by opl posed side walls 49-49andbyan outer end wall 58. installed in the chaser-receiving notch-48 ofthe chaser-mounting member 38 Aifs a substan-V tially-rectangular chaser5l having `thread-cut ting teeth 52 atitsY inner end and transverselypiercedrby a passage 53 which is flared at VAone end to Aprovide a`conical V cam-surface 54. f Substantially in line with the passage` 53through the chaser 5| the chaser-mounting member 38 '1S' formed, with a`t1 nrtd 1inte 55 ,inte 'which is The clamping-screws 46 alsoserve Ythreaded the threaded shank 58 of a chaser-seat?V ing screw generallydesignated by the reference character 51 and including apolygonallysocketed head-portion 58 joined to the threaded shank 56 by aconical cam-surface 59. The head 58 of the screw 51 is located in a bore55a in the wall of the member 38 opposite the threaded bore 55 and thecam-surface 59 of the said screw is adapted to engage with the conicalcam-surface 54 in the chaser 5l toforce the said chaser out- Vwardlyfirmly into engagement with the end wall 50 of the notch 48 and intofirm engagement with Athe opposite wall 49 of the said member (Fig. 5)..

The outer end of the chaser 5I opposite Vthe thread-cutting teeth52risformed with a transverse notch 68 into which extends the flattened endof a stabilizing-stud 8| rigidly positioned'in a socket 62 openingthrough the end wall 59 of the notch 48 in the chaser-mounting member38. The projecting flattened jend of the stabilizing'- studl 8| byprojecting into the notch 88 in the chaser 5| serves to prevent theouter end of the chaser from being cocked forwardly under the stressdevelopedV when the thread-cutting teeth 52 of the chaser are in action.i Y

In all of the gures preceding Fig. 6 the chasermounting member 38 isshown as adjusted to `the `be moved inwardly by i'lrst Yloosening the'clamping-bolts 46 sufficiently to permit the said mounting-members to bemoved forwardly with respect to their complemental base-member 23adistance lll.Y

suicient to disengage the locating-teeth 39 of Y IfY desired theradially inwardly relative to their respective base.'-

members 23 a distance corresponding to the spacing of the locating-teethto thus provide inthe particular structure chosen'for illustration forthe cuttingof threadsof1/2 diameter as shown inFig.6.v 'f Y 'f When thechaser-mounting members 38 have been moved the ,desiredV distanceY(within the yrange provided by the slotsY 41) the locating-teeth 39 and43 are reengaged and the clamping-'screws 148 tightenedto re-lock themembers 38 and 23 together'into a unit. vA suitable chaserl ofsubstantially the .same over-all dimensions as the chaser 5| may nowbe'installed in the chaserreceiving notches 48 in place ofY the saidchasers 5I, if desired.

As thus constructed and arranged, the two-part VVchaser-holdersprovidefor increments of adjiist`l` lmentinr a `radial directioncorresponding tothe spacing of locating-teeth 39 and 40 therebymaking'it possible to employ'chaserfs of substantially the same lengthfor cutting threads o'fvar'ious Y standard diameters without requiring'thef replacement of the chaser-holders by 'other chaserholders.Furthermore byproviding chaser-holdv with a die-head equippedwithholders., ofthe present invention for cutting various thread diametersWithin the range of the particular diehead. In the instance shown anddescribed' the Chaser-holder provides for adjustments in increments ofl" though greater or lesser increments may be provided for but in theevent that it is desired to cut a thread diameter intermediate theincrements referred to the Chaser-blanks may be ground back anappropriate amount. It may be here noted that in the usual manner ofself-opening die-heads, the adjusting-nut 32 provides for adjusting theChaser-holders asa whole within a limited range.

In addition to other advantages to chaserholders as above described, itmay here be noted that in the event that it is desired to make achange-over from a set-up for cutting right-hand threads to a set-up forcutting left-hand threads or vice versa, it is necessary only to replacethe Chaser-mounting members 38 and substitute in conjunction with theremaining base-members 23 a similar Chaser-mounting member having itsChaser-seating screw 51 extending therethrough in the opposite directionfrom that of the members 38.

The invention may be carried out in other specic ways than those hereinset forth without departing from the spirit and essentialcharacteristics of the invention, and the present embodiments are,therefore, to be considered in all respects as illustrative and notrestrictive, and all changes coming within the meaning and equivalencyrange of the appended claims are intended to be embraced therein.

I claim:

1. A composite Chaser-holder for thread-cutting tools, comprising: abase-member having means thereon for intertting with a die-head; acomplemental Chaser-carrying member carried by the said base-member withycapacity for bodily rectilinearv adjustment with respect thereto, thedivision between the two said members being in a plane substantiallyparallel with the front face of the die-head structure; and lockingmeansextending between the two said members and binding the same into aunitary structure.

2. A composite chaser-holder for thread-cutting tools, comprising: abase-member having means thereon for interi'ltting with a die-head; acomplemental Chaser-carrying member having an inwardly-openingChaser-receiving socket and carried by the said base-member withcapacity for bodily rectilinear adjustment with respect thereto, thedivision between the two said members being in a plane substantiallyparallel with the front face of the die-head structure; andlocking-means extending between the two said members and binding thesame into a unitary structure.

3. A composite Chaser-holder for thread-cutting tools, comprising: abase-member having means thereon for interftting with a die-head; acomplemental Chaser-carrying member having an inwardly-openingchaser-receiving notch'and being carried by the said base-member withcapacity for bodily rectilinear adjustment with respect thereto,Y thedivision between the two said members being in a plane substantiallyparallel with the front face of the die-head structure; andlocking-means extending between the said members and binding the sameinto a unitary structure.

4. A composite Chaser-holder for thread-cutting tools, comprising: abase-member having means thereon for interltting with a die-head; a

'complemental chaser-carrying member having an inwardly-openingChaser-receiving notch extending thereacross from its forward to itsrear face, the said 'Chaser-carrying member being carried by the saidbase-member with capacity for bodily adjustment with respect thereto andhaving the rear terminus of its Chaser-receivingY wardly-projecting tangfor intertting with a die-head and also having a locating-shoulderextending transversely with respect to the said tang for engagement witha locating-shoulder on the ysaid Chaser-carrying member, and the saidchaser-carrying member having a Chaser-receiving seat and alocating-shoulder engageable with the locating-shoulder of the saidbase-member.

6. A Ycomposite Chaser-holder for thread-cutting tools, comprising: abase-member; a complemental Chaser-carrying member carried by the saidbase-member with capacity for bodily rectilinear adjustment withrespectthereto; and locking-means extending between the two said members andbinding the same into a unitary structure; the said base-member having arearwardlyprojecting tang for interiitting with a die-.head and alsohavingv a plurality of 1ocatingteetheX tending transversely with respectto the said tang for engagement with a plurality of locating-teeth onthe said Chaser-carrying member; and the said Chaser-carrying memberhaving a chaserreceiving seat and the plurality of locating-teethengageable with the locating-teeth of the said base-member.

7. A composite chaser-holder for thread-cutting tools, comprising: abase-member having a rearwardly-projecting tang for interfitting with adie-head and also having a locating-shoulder extending transversely withrespectk to the said tang for engagement with a locating-shoulder on thesaid Chaser-carrying member; a complemental Chaser-carrying membercarried by the said base-member with capacity for bodily rectilinearadjustment with respect thereto and having a Chaser-receiving seat and alocating-shoulder engageable with the locating-shoulder of the saidbase-member; and locking-means extending between the two said membersand binding the same into a unitary structure; the division between thetwo said members being in a plane substantially parallel with the frontface of th die-head structure.

8. A composite Chaser-holder for thread-cutting tools, comprising: abase-member having a rearwardly-projecting tang for intertting with adie-head and also having a plurality of locating-teeth extendingtransversely with respect to the said tang for engagement with aplurality of locating-teeth on the said Chaser-carrying member; acomplemental Chaser-carrying member carried b-y the said base-memberwith capacity for bodily rectilinear adjustment with respect thereto andhaving a Chaser-receiving seat and a plurality of locating-teethengageable with the locating-teeth of the said base-member; and

Y member also of sector shape and carried by the locking-means extendingbetween the two said members and binding the same into a unitarystructure; the divisionbetween the two said members being in-a planesubstantially parallel with l the front face of the die-head structure.

9. A composite; chaser-holder for thread-cutting tools, comprising: abase-member having a xed rearwardly-projecting tang rigid therewith forinterrlttingv with adie-head and having a forward sector-shapedstabilizing portion extending laterally on each of the respectiveopposite sides of `the said tang and engageable with the forward face ofVa die-head; a complemental Chaser-carrying member also of sector shapeand carried by the said base-member with capacity for bodily rectilinearadjustmentrwith respect theretoj andelocking-means extending between thetwo said sector-shaped members on each -of the respective opposite sidesof the tang of the said base-member and binding-the said members into a'unitary structure. Y

10. A composite Chaser-holder for thread-cutting tools, comprising:aV-base-member having a xed rearwardly-projecting tang rigid therewithfor intertting with adie-head and having a rforward sector-shapedstabilizing portion eX- tending laterally on each of the respectiveopposite sides rof the said tang and engageable with the forward face ofaVdie-head; a complemental Chaser-carrying member carried bythe saidbasemember with capacity for adjustment with re-f spect thereto, thedivision between the* two said members being in; a plane substantiallyparrallel with the front face ofthe die-head structure; andlocking-means extending between the two said members'on-l each of therespective oppo- `Von each ofthe respective opposite sides 'of/the' saidtang and engageable with the forwardr face of a die-head; a.complemental chaser-carrying said base-member withY capacity foradjustment with respect thereto, the division between the Y two saidsector-shaped members being in a plane substantially parallelV with thefrontface of the i die-head structure; and locking-means extending Uvf,

betweenv the two said members on each of the l respective opposite sidesof the tangof the said base-member and binding the said members into aunitary structure. Y n V12. A composite Chaser-holderforthread-cutlocated on the opposite sides of the said tang.

ting tools,'comprising`: Va base-member having a forwardly-projectingtang for interfitting with a die-head and also having alocating-shoulder ex- Y tending transversely with respect to said'tangfor engagement with a locating-shoulder on the said Chaser-carryingmember; a complemental chasercarrying member carriedby the saidbase-member with capacity for bodily rectilinear adjust-` ment withrespect thereto and having a chaserreceiving seat and alocating-shoulderengageable with'the locating-shoulder of the said basemember; and a pairof locking-screws extending,

between the two said members and binding the same into Va unitarystructure and respectively 13. A composite Chaser-holder forthread-cutting tools, comprising: a base-member havingarearwardly-projecting tang for intertting with a die-head and having aforward sector-shaped Y portion extending laterally on each of therespective opposite sides of the said tang and engageableiwith theforwardV face of a die-head; aV complemental chaser-carrying'member alsoof sector shape Vand carried by the said base-member with capacityforadjustment with respect thereto, the division between the two saidsectorshaped members being in a plane substantially parallel with thefront face of the die-head structure; and a pair "oflocking-serewsrespectively located on the opposite sides of the tang of the saidbase-member and extending betweenthe two said members to bindjthe sameinto a unitaryA structure, f f n 14. A composite Chaser-holder forthread-cutting tools, comprising: a base-member Vhaving arearwardly-projecting tangfor interiitting with a die-head and having aforward sector-shaped portion extendingv laterally oneachV of theY re- Yspective opposite sidesH oi the said tang and formed in its Yforwardfacewith'a substantiallyradial locating-groove; a.l locating-stud havinglocating-teeth thereonV and mounted in the said base-member in positionto have its locatingof; a complemental Chaser-carrying member also ofsector shape and carried by the said baseteeth projectingl into thelocating-'groove there- Y 15 member with capacity for adjustment withrespect thereto and formedfon its inner face with a guide-rib formedwith a plurality of locatingteeth andprojecting intothe locating-grooveVof the said base-member into engagement with the locating-teeth on thelocating-stud therein; and

Y a pair of locking-screws one of which extends between the saidsector-shaped members on each of the respective-opposite sides ofthesaid guider groove and the said guide-rib thereof.

ALBERT 1r. BREITENSTEIN,

